Entropy and heat transfer investigation of Casson–Maxwell, Casson–Jeffrey, and Casson–Oldroyd-B binary nanofluids in a parabolic trough solar collector: a comparative study

Abstract In this paper, we compared copper-engine oil Casson–Maxwell, Casson–Jeffrey, and Casson–Oldroyd-B binary nanofluids in a parabolic trough solar collector. Using appropriate similarity variables, the partial differential equations governing nanofluid flow were converted into ordinary equations. The resulting nonlinear systems solved using shooting method. numerical results presented graphical tabular forms. We investigated effects of different parameters controlling on velocity, temperature, entropy generation, skin friction, local Nusselt number nanofluids. Overall, Casson–Maxwell Casson–Jeffrey models had better efficiency than model.